Re: [v6ops] How do you solve 3GPP issue if neither operator nor handset supports PD?

Philip Homburg <> Tue, 24 November 2020 12:34 UTC

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Subject: Re: [v6ops] How do you solve 3GPP issue if neither operator nor handset supports PD?
From: Philip Homburg <>
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In-reply-to: Your message of "Tue, 24 Nov 2020 13:17:24 +0100 ." <>
Date: Tue, 24 Nov 2020 13:34:41 +0100
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In your letter dated Tue, 24 Nov 2020 13:17:24 +0100 you wrote:
>In the P2P Ethernet/3GPP case it says:
> This prefix is not used on the link between us.
> The prefix is dedicated to you, and I promise to install a route like:
>  ipv6 route <prefix> p2p-interface | interface, NH pointing at you.
> You can if you like configure an address on the interface on the upstream lin
> as the router will forward traffic to anything in that prefix blindly.
> (you aren't strictly doing SLAAC at that point though.)

In my experience, many true point-to-point links (such as ppp, but also
tunnels) are like this.

The reason is that in theory you should do neighbor discovery even if a link
has no L2 addresses. I found that many implementations just don't react
to an NS or send any themselves.

So all traffic is just sent to the other side of the link. I.e., the route
could actually point to the link, but you can't really tell the difference.

In theory you could try to see if the router has an address on the link, but
I never tried that experiment.